1. Field of the Disclosure
This disclosure relates generally to drill bits and systems for using the same for drilling wellbores.
2. Background Of The Art
Oil wells (also referred to as “wellbores” or “boreholes”) are drilled with a drill string that includes a tubular member having a drilling assembly (also referred to as the “drilling assembly” or “bottomhole assembly” or “BHA”) which includes a drill bit attached to the bottom end thereof. The drill bit is rotated by rotating the drill string from a surface location and/or by a drilling motor (also referred to as the “mud motor”) in the BHA to disintegrate the rock formation to drill the wellbore. The BHA includes devices and sensors for providing information about a variety of parameters relating to downhole operations, including tool face control of the BHA. A large number of wellbores are contoured and may include one or more vertical sections, straight inclined sections and curved sections (up or down). The weight-on-bit (WOB) applied on the drill bit while drilling a curved section (up or down) is often increased and the drill bit rotation speed (RPM) decreased as compared to the WOB and RPM used while drilling a vertical or straight inclined section. Control of the tool face is an important parameter for drilling smooth curved sections. A relatively aggressive drill bit (high cutter depth of cut) is generally desirable for drilling vertical or straight sections while a relatively less aggressive drill bit (low cutter depth of cut) is often desirable for drilling curved sections. The drill bits, however, are typically designed with cutters having the same depth of cut, i.e., a constant aggressiveness.
Therefore, it is desirable to provide a drill bit that will exhibit less aggressiveness during drilling of a curved section of a wellbore and more aggressiveness during drilling of a straight section of the wellbore.